Updated November 23, 2015 at 3:31 PM;Posted November 22, 2015 at 2:50 PM

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A French flag placed in front of flowers outside 'The Petit Cambodge' in Paris Sunday, Nov. 22, more than a week after the Paris terrorist attacks. French President Francois Hollande will preside over a national ceremony on Nov. 27 honoring the victims of the deadliest attacks on France in decades.
(Laurent Cipriani, Associated Press)

After the horrible terrorist attacks on Paris, French President Francois Hollande swore revenge, saying France would "be merciless toward the barbarians of the Islamic State group."

Republican presidential candidates called for a highly aggressive military response from the United States. For example, Texas Sen. Ted Cruz called for the United States to abandon its commitment to strive for "zero tolerance for civilian casualties" when facing terrorists who "have such utter disregard for innocent life."

Former Florida Gov. Jeb Bush called the attacks a sign of "an organized effort to destroy Western civilization." Florida Sen. Marco Rubio called for a "substantially increased commitment" of U.S. ground troops in the war against ISIS.

This is exactly what ISIS wants. This terrorist state wants to be the target of "merciless" revenge by French and other Western forces. ISIS leaders would love to see the United States publicly abandon its commitment to avoiding civilian deaths in our airstrikes. U.S. ground troops actively fighting ISIS, instead of the current situation of U.S. special forces training and advising local Kurdish fighters, would be a generous gift to ISIS.

Why? Because any of these changes in government policy would radicalize more Muslims. So does rhetoric from Western political figures pitting a "Western civilization" against Islam, or promising "merciless" revenge.

Causing Muslims to grow more radical moves them to contribute resources to anti-Western causes, including ISIS. There is a spectrum of radicalization, and aggressive actions we take result in some Muslims moving further along the spectrum.

For instance, consider what happens when Muslim media report an airstrike by Western forces that kills civilians. At any point, myriad Muslim youths are angry at the Western intervention into Syria. For a number of them -- say, 100 -- the report will be the thing that tips them over from anger to outrage, and they will decide to join ISIS.

Let's say 5 percent get trained in ISIS camps as suicide bombers. That means five new suicide bombers per report of an airstrike killing civilians, ready to wreak havoc on the United States or other Western countries.

That same report will radicalize Muslims living in the West, making them willing to hide and otherwise support suicide bombers. It will also cause Muslims to contribute money to ISIS to fund its activities, including terrorism. This is the mix of ingredients required for the kind of mass-scale, coordinated terrorist attack that struck Paris.

By responding aggressively with airstrikes and angry rhetoric, we let the terrorists win. Even worse, by getting our ground troops directly involved in fighting ISIS, we would be taking the path to another Iraq.

So what should we do?

We should not act immediately. We need to go against our intuitive emotional desire for revenge. We need to step back and assess the situation intentionally.

Recent research shows that after any emotionally powerful event, in politics or private life, our brains tend to assign too much weight to that event, compared with what is really important to us. This thinking error is called attentional bias.

To fight this thinking error, we should consider what are our actual long-term goals and how to achieve them in the best possible manner.

Our actual goals are to decrease the likelihood of terrorist attacks, not to increase their likelihood through an aggressive response. To achieve our goals, a good question to ask here is, "What would ISIS not want us to do?"

ISIS would not want us to take quiet, covert actions that would avoid radicalizing everyday Muslims. ISIS would not want our top political figures to make powerful, courageous, politically unpopular statements that all Muslims are not to blame for this attack, but only a small group of radicals.

ISIS would not want us to reach out to Muslim leaders in our communities and around the world who condemned the Paris attacks and work together against the radicals.

Let us set aside our emotional desire for revenge, however difficult, and take the hard road that will achieve our long-term goals. Otherwise, we let the terrorists win.

Gleb Tsipursky is a tenure-track professor at Ohio State University and runs a nonprofit that helps people reach their goals using science.